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Getting more battery power for your computer

Do external batteries make sense? Are knock-off internal batteries safe? A couple of recent articles address these questions.

James Kendrick, one of the bloggers at, recently wrote: "Mobile computer users will tell you that the number one need they have is for sufficient battery power." There are a few ways laptop computer users can get more battery power for their computers:

  1. Buy a larger battery designed specifically for your computer. When buying many, if not most, laptop computers, you should have a choice of batteries. Higher-capacity batteries are physically bigger, cost more, and may very well protrude either vertically or horizontally.
  2. If you find you need more power for a laptop computer you already own, you can buy a second battery. One downside to this approach is that the computer has to be powered off to switch batteries. Then too, there are safety concerns when carrying around an internal battery.
  3. Yet another option involves an external battery pack that plugs into the same port on the laptop that the AC power cord does.

If you are interested in buying an internal battery, either to have as a spare when traveling or simply to replace a dying one, then check out "Cheap laptop batteries: Good deal or risky business?" by Brian Nadel of Computerworld. As Nadel explains it:

"There are two basic types of notebook batteries: the brand-name batteries that the manufacturer sells and the aftermarket batteries that are available from third-party resellers -- often for a significantly lower price ... We all want to save money, but not if it puts our notebooks at risk. Buying an aftermarket battery often goes against the advice of laptop manufacturers, and in some cases can even void the warranty. Is it worth it to save a few bucks?"

He tested three replacement batteries for a MacBook Pro and another three for a ThinkPad R50. His conclusion? "The aftermarket replacements proved to be just as good and reliable as the originals." That said, there is a big difference in aftermarket batteries; the article offers buying tips.

One issue with having two batteries is that only one can be charging at a time. But, every problem is a marketing opportunity, and a recent posting at Liliputing describes chargers you can buy for an Asus Eee PC that let you externally charge an internal battery.

In "External battery packs can power that notebook for hours", Kendrick discusses his experiences. In brief, external batteries offer a lot of power but at a price. As for power, he says they "can power most laptops for 8-10 hours." As for price, the two companies he mentions offer models priced at $200 and $300. Not cheap, but as Kendrick says, when you need them you really need them.

See a summary of all my Defensive Computing postings.